This invention relates to a modular printhead. More particularly, the invention relates to the assembly of such a modular printhead. Specifically, this invention relates to a printhead assembly.
The applicant has previously proposed the use of a pagewidth printhead to provide photographic quality printing. However, manufacturing such a pagewidth printhead having the required dimensions is problematic in the sense that, if any nozzle of the printhead is defective, the entire printhead needs to be scrapped and replaced.
Accordingly, the applicant has proposed the use of a pagewidth printhead made up of a plurality of small, replaceable printhead modules which are arranged in end-to-end relationship. The advantage of this arrangement is the ability to remove and replace any defective module in a pagewidth printhead without having to scrap the entire printhead.
It is also necessary to accommodate thermal expansion of the individual modules in the assembly constituting the pagewidth printhead to ensure that adjacent modules maintain their required alignment with each other.
According to the invention, there is provided a printhead assembly which includes
a body defining a seat for a printhead and having a dividing member;
a plurality of fluid storage galleries arranged on one side of the dividing member;
a plurality of feed passages arranged on an opposed side of the dividing member, each feed passage having a first end in communication with one of the galleries and an opposed end opening out into the seat; and
a printhead mounted in said seat such that fluid fed from the galleries is supplied to at least one printhead chip of the printhead.
The dividing member may be in the form of a wall or core member with a plurality of separating elements projecting from one side of the wall, the separating elements defining a plurality of separate channels. The body may include a closure member secured to the wall to close off the channels to define the galleries.
A plurality of discrete canals may be formed in spaced relationship on an opposed side of the wall. The body may include a cover member which closes off the canals to define the feed passages.
An outer surface of the cover member may carry conductive elements, the conductive elements providing control signals to said at least one printhead chip. The conductive elements may be formed on said outer surface of the cover member by hot stamping during molding of the cover member. Preferably, the printhead includes a plurality of printhead modules arranged in end-to-end relationship, each module carrying a printhead chip so that fluid is supplied to each of the printhead chips.